Returns a set of temporary security credentials (consisting of an
access key ID, a secret access key, and a security token) that you can
use to access AWS resources that you might not normally have access
to. Typically, you use AssumeRole for cross-account
access or federation.

Important: You cannot call AssumeRole by using
AWS account credentials; access will be denied. You must use IAM user
credentials or temporary security credentials to call
AssumeRole .

For cross-account access, imagine that you own multiple accounts and
need to access resources in each account. You could create long-term
credentials in each account to access those resources. However,
managing all those credentials and remembering which one can access
which account can be time consuming. Instead, you can create one set
of long-term credentials in one account and then use temporary
security credentials to access all the other accounts by assuming
roles in those accounts. For more information about roles, see
Roles
in Using IAM .

For federation, you can, for example, grant single sign-on access to
the AWS Management Console. If you already have an identity and
authentication system in your corporate network, you don't have to
recreate user identities in AWS in order to grant those user
identities access to AWS. Instead, after a user has been
authenticated, you call AssumeRole (and specify the role
with the appropriate permissions) to get temporary security
credentials for that user. With those temporary security credentials,
you construct a sign-in URL that users can use to access the console.
For more information, see
Scenarios for Granting Temporary Access
in Using Temporary Security Credentials .

The temporary security credentials are valid for the duration that you
specified when calling AssumeRole , which can be from 900
seconds (15 minutes) to 3600 seconds (1 hour). The default is 1 hour.

Optionally, you can pass an IAM access policy to this operation. If
you choose not to pass a policy, the temporary security credentials
that are returned by the operation have the permissions that are
defined in the access policy of the role that is being assumed. If you
pass a policy to this operation, the temporary security credentials
that are returned by the operation have the permissions that are
allowed by both the access policy of the role that is being assumed,
and the policy that you pass. This gives you a way to further
restrict the permissions for the resulting temporary security
credentials. You cannot use the passed policy to grant permissions
that are in excess of those allowed by the access policy of the role
that is being assumed. For more information, see
Permissions for AssumeRole
in Using Temporary Security Credentials .

To assume a role, your AWS account must be trusted by the role. The
trust relationship is defined in the role's trust policy when the role
is created. You must also have a policy that allows you to call
sts:AssumeRole .

Using MFA with AssumeRole

You can optionally include multi-factor authentication (MFA)
information when you call AssumeRole . This is useful for
cross-account scenarios in which you want to make sure that the user
who is assuming the role has been authenticated using an AWS MFA
device. In that scenario, the trust policy of the role being assumed
includes a condition that tests for MFA authentication; if the caller
does not include valid MFA information, the request to assume the role
is denied. The condition in a trust policy that tests for MFA
authentication might look like the following example.

"Condition": {"Null": {"aws:MultiFactorAuthAge": false}}

For more information, see
Configuring MFA-Protected API Access
in the Using IAM guide.

To use MFA with AssumeRole , you pass values for the
SerialNumber and TokenCode parameters. The
SerialNumber value identifies the user's hardware or
virtual MFA device. The TokenCode is the time-based
one-time password (TOTP) that the MFA devices produces.

The policy parameter is optional. If
you pass a policy, the temporary security credentials that are
returned by the operation have the permissions that are allowed by
both the access policy of the role that is being assumed,
and the policy that you pass. This gives you a way to
further restrict the permissions for the resulting temporary security
credentials. You cannot use the passed policy to grant permissions
that are in excess of those allowed by the access policy of the role
that is being assumed. For more information, see Permissions
for AssumeRole in Using Temporary Security Credentials.

A unique identifier that is used by third parties to assume a role in
their customers' accounts. For each role that the third party can
assume, they should instruct their customers to create a role with the
external ID that the third party generated. Each time the third party
assumes the role, they must pass the customer's external ID. The
external ID is useful in order to help third parties bind a role to
the customer who created it. For more information about the external
ID, see About the External ID in Using Temporary
Security Credentials.

The identification number of the MFA device that is associated with
the user who is making the AssumeRole call. Specify this
value if the trust policy of the role being assumed includes a
condition that requires MFA authentication. The value is either the
serial number for a hardware device (such as
GAHT12345678) or an Amazon Resource Name (ARN) for a
virtual device (such as
arn:aws:iam::123456789012:mfa/user).

The value provided by the MFA device, if the trust policy of the role
being assumed requires MFA (that is, if the policy includes a
condition that tests for MFA). If the role being assumed requires MFA
and if the TokenCode value is missing or expired, the
AssumeRole call returns an "access denied" error.

The policy parameter is optional. If
you pass a policy, the temporary security credentials that are
returned by the operation have the permissions that are allowed by
both the access policy of the role that is being assumed,
and the policy that you pass. This gives you a way to
further restrict the permissions for the resulting temporary security
credentials. You cannot use the passed policy to grant permissions
that are in excess of those allowed by the access policy of the role
that is being assumed. For more information, see Permissions
for AssumeRole in Using Temporary Security Credentials.

The policy parameter is optional. If
you pass a policy, the temporary security credentials that are
returned by the operation have the permissions that are allowed by
both the access policy of the role that is being assumed,
and the policy that you pass. This gives you a way to
further restrict the permissions for the resulting temporary security
credentials. You cannot use the passed policy to grant permissions
that are in excess of those allowed by the access policy of the role
that is being assumed. For more information, see Permissions
for AssumeRole in Using Temporary Security Credentials.

The policy parameter is optional. If
you pass a policy, the temporary security credentials that are
returned by the operation have the permissions that are allowed by
both the access policy of the role that is being assumed,
and the policy that you pass. This gives you a way to
further restrict the permissions for the resulting temporary security
credentials. You cannot use the passed policy to grant permissions
that are in excess of those allowed by the access policy of the role
that is being assumed. For more information, see Permissions
for AssumeRole in Using Temporary Security Credentials.

The policy parameter is optional. If
you pass a policy, the temporary security credentials that are
returned by the operation have the permissions that are allowed by
both the access policy of the role that is being assumed,
and the policy that you pass. This gives you a way to
further restrict the permissions for the resulting temporary security
credentials. You cannot use the passed policy to grant permissions
that are in excess of those allowed by the access policy of the role
that is being assumed. For more information, see Permissions
for AssumeRole in Using Temporary Security Credentials.

The policy parameter is optional. If
you pass a policy, the temporary security credentials that are
returned by the operation have the permissions that are allowed by
both the access policy of the role that is being assumed,
and the policy that you pass. This gives you a way to
further restrict the permissions for the resulting temporary security
credentials. You cannot use the passed policy to grant permissions
that are in excess of those allowed by the access policy of the role
that is being assumed. For more information, see Permissions
for AssumeRole in Using Temporary Security Credentials.

Returns a reference to this object so that method calls can be chained together.

The policy parameter is optional. If
you pass a policy, the temporary security credentials that are
returned by the operation have the permissions that are allowed by
both the access policy of the role that is being assumed,
and the policy that you pass. This gives you a way to
further restrict the permissions for the resulting temporary security
credentials. You cannot use the passed policy to grant permissions
that are in excess of those allowed by the access policy of the role
that is being assumed. For more information, see Permissions
for AssumeRole in Using Temporary Security Credentials.

Returns:

A reference to this updated object so that method calls can be chained
together.

A unique identifier that is used by third parties to assume a role in
their customers' accounts. For each role that the third party can
assume, they should instruct their customers to create a role with the
external ID that the third party generated. Each time the third party
assumes the role, they must pass the customer's external ID. The
external ID is useful in order to help third parties bind a role to
the customer who created it. For more information about the external
ID, see About the External ID in Using Temporary
Security Credentials.

Constraints:Length: 2 - 96Pattern: [\w+=,.@:-]*

Returns:

A unique identifier that is used by third parties to assume a role in
their customers' accounts. For each role that the third party can
assume, they should instruct their customers to create a role with the
external ID that the third party generated. Each time the third party
assumes the role, they must pass the customer's external ID. The
external ID is useful in order to help third parties bind a role to
the customer who created it. For more information about the external
ID, see About the External ID in Using Temporary
Security Credentials.

A unique identifier that is used by third parties to assume a role in
their customers' accounts. For each role that the third party can
assume, they should instruct their customers to create a role with the
external ID that the third party generated. Each time the third party
assumes the role, they must pass the customer's external ID. The
external ID is useful in order to help third parties bind a role to
the customer who created it. For more information about the external
ID, see About the External ID in Using Temporary
Security Credentials.

Constraints:Length: 2 - 96Pattern: [\w+=,.@:-]*

Parameters:

externalId A unique identifier that is used by third parties to assume a role in
their customers' accounts. For each role that the third party can
assume, they should instruct their customers to create a role with the
external ID that the third party generated. Each time the third party
assumes the role, they must pass the customer's external ID. The
external ID is useful in order to help third parties bind a role to
the customer who created it. For more information about the external
ID, see About the External ID in Using Temporary
Security Credentials.

A unique identifier that is used by third parties to assume a role in
their customers' accounts. For each role that the third party can
assume, they should instruct their customers to create a role with the
external ID that the third party generated. Each time the third party
assumes the role, they must pass the customer's external ID. The
external ID is useful in order to help third parties bind a role to
the customer who created it. For more information about the external
ID, see About the External ID in Using Temporary
Security Credentials.

Returns a reference to this object so that method calls can be chained together.

Constraints:Length: 2 - 96Pattern: [\w+=,.@:-]*

Parameters:

externalId A unique identifier that is used by third parties to assume a role in
their customers' accounts. For each role that the third party can
assume, they should instruct their customers to create a role with the
external ID that the third party generated. Each time the third party
assumes the role, they must pass the customer's external ID. The
external ID is useful in order to help third parties bind a role to
the customer who created it. For more information about the external
ID, see About the External ID in Using Temporary
Security Credentials.

Returns:

A reference to this updated object so that method calls can be chained
together.

The identification number of the MFA device that is associated with
the user who is making the AssumeRole call. Specify this
value if the trust policy of the role being assumed includes a
condition that requires MFA authentication. The value is either the
serial number for a hardware device (such as
GAHT12345678) or an Amazon Resource Name (ARN) for a
virtual device (such as
arn:aws:iam::123456789012:mfa/user).

Constraints:Length: 9 - 256Pattern: [\w+=/:,.@-]*

Returns:

The identification number of the MFA device that is associated with
the user who is making the AssumeRole call. Specify this
value if the trust policy of the role being assumed includes a
condition that requires MFA authentication. The value is either the
serial number for a hardware device (such as
GAHT12345678) or an Amazon Resource Name (ARN) for a
virtual device (such as
arn:aws:iam::123456789012:mfa/user).

The identification number of the MFA device that is associated with
the user who is making the AssumeRole call. Specify this
value if the trust policy of the role being assumed includes a
condition that requires MFA authentication. The value is either the
serial number for a hardware device (such as
GAHT12345678) or an Amazon Resource Name (ARN) for a
virtual device (such as
arn:aws:iam::123456789012:mfa/user).

Constraints:Length: 9 - 256Pattern: [\w+=/:,.@-]*

Parameters:

serialNumber The identification number of the MFA device that is associated with
the user who is making the AssumeRole call. Specify this
value if the trust policy of the role being assumed includes a
condition that requires MFA authentication. The value is either the
serial number for a hardware device (such as
GAHT12345678) or an Amazon Resource Name (ARN) for a
virtual device (such as
arn:aws:iam::123456789012:mfa/user).

The identification number of the MFA device that is associated with
the user who is making the AssumeRole call. Specify this
value if the trust policy of the role being assumed includes a
condition that requires MFA authentication. The value is either the
serial number for a hardware device (such as
GAHT12345678) or an Amazon Resource Name (ARN) for a
virtual device (such as
arn:aws:iam::123456789012:mfa/user).

Returns a reference to this object so that method calls can be chained together.

Constraints:Length: 9 - 256Pattern: [\w+=/:,.@-]*

Parameters:

serialNumber The identification number of the MFA device that is associated with
the user who is making the AssumeRole call. Specify this
value if the trust policy of the role being assumed includes a
condition that requires MFA authentication. The value is either the
serial number for a hardware device (such as
GAHT12345678) or an Amazon Resource Name (ARN) for a
virtual device (such as
arn:aws:iam::123456789012:mfa/user).

Returns:

A reference to this updated object so that method calls can be chained
together.

The value provided by the MFA device, if the trust policy of the role
being assumed requires MFA (that is, if the policy includes a
condition that tests for MFA). If the role being assumed requires MFA
and if the TokenCode value is missing or expired, the
AssumeRole call returns an "access denied" error.

Constraints:Length: 6 - 6Pattern: [\d]*

Returns:

The value provided by the MFA device, if the trust policy of the role
being assumed requires MFA (that is, if the policy includes a
condition that tests for MFA). If the role being assumed requires MFA
and if the TokenCode value is missing or expired, the
AssumeRole call returns an "access denied" error.

The value provided by the MFA device, if the trust policy of the role
being assumed requires MFA (that is, if the policy includes a
condition that tests for MFA). If the role being assumed requires MFA
and if the TokenCode value is missing or expired, the
AssumeRole call returns an "access denied" error.

Constraints:Length: 6 - 6Pattern: [\d]*

Parameters:

tokenCode The value provided by the MFA device, if the trust policy of the role
being assumed requires MFA (that is, if the policy includes a
condition that tests for MFA). If the role being assumed requires MFA
and if the TokenCode value is missing or expired, the
AssumeRole call returns an "access denied" error.

The value provided by the MFA device, if the trust policy of the role
being assumed requires MFA (that is, if the policy includes a
condition that tests for MFA). If the role being assumed requires MFA
and if the TokenCode value is missing or expired, the
AssumeRole call returns an "access denied" error.

Returns a reference to this object so that method calls can be chained together.

Constraints:Length: 6 - 6Pattern: [\d]*

Parameters:

tokenCode The value provided by the MFA device, if the trust policy of the role
being assumed requires MFA (that is, if the policy includes a
condition that tests for MFA). If the role being assumed requires MFA
and if the TokenCode value is missing or expired, the
AssumeRole call returns an "access denied" error.

Returns:

A reference to this updated object so that method calls can be chained
together.